The Contractor shall provide statistical programming, data processing, and data management support for the research projects being conducted by the Biometry Branch. This support includes the analysis of large sets of medical data often involving complex statistical analysis, and requires the Contractor to use sophisticated data handling and analytic techniques, and extensive plotting by digital computer. The facilities of the National Institutes of Health/Division of Computer Research and Technology (NIH/DCRT) will be used for all computer processing. Not all of the specific projects to be supported under this contract are listed or can be predicted at this time. These projects will vary in size, complexity and duration; they range from long-term projects to special studies. These include development and maintenance of multi-institutional collaborative screening or clinical trials, biostatistical studies on various aspects of cancer using one or more data files, development of statistical and epidemiological methodology for carrying out such research projects, pilot or feasibility screening and/or prevention trials, the conduct of epidemiologic and biostatistical studies of cancer screening, and cancer prevention and control. 1. In the support of new studies and systems, the Contractor shall perform manual data editing, accounting, and keypunch functions and write computer edit, update and analysis programs associated with various "live" data collection studies. The Contractor shall be responsible for the design and implementation of the computer software system including the selection of the appropriate high level programming language. 2. In the support of completed and on going studies, the Contractor shall maintain existing systems and code, test and implement modifications to these systems. The modifications shall be made to resolve technical problems, to incorporate changes requested by NCI researchers and to conform to revisions in the NIH computer center data processing environment. 3. The Contractor shall develop new software systems. The Contractor shall maintain and continue to develop the system of statistical programs (i.e. The Interactive Statistical Analysis System) which resides on the DCRT DEC-10 computer. The Contractor shall write additional computer programs to support the research activities of the Branch in the development of statistical methodology.